Posted 11-19-2004 at 04:38:51
[Reply] [No Email]I have an '89 Chevy halfton. Fine truck but the ampmeter flucuates with the turning signals and with the heater fan on Hi it drops and doesn't recover. Normally it shows 14 amps with the fan on hi it drops to about 10. After the fan is turned off or down it will charge at about 16. The alternator was replaced about a year ago. Anyone have any idea what the problem maybe? And before you start no I don't want a Ford or a Dodge. Thanks.

toolman

Posted 11-19-2004 at 12:40:50
[Reply] [No Email]with a ford or a dodge you would have to worry about it , but not a chevy, they are related to timex.

MW/Ks

Posted 11-19-2004 at 07:02:59
[Reply] [No Email]It is a ground problem. See it all the time.

Bob

Posted 11-19-2004 at 05:07:04
[Reply] [No Email]You don't have an "ampmeter", you have a voltmeter.

A noticable fluctuation with the turn signals "ON" is normal.

As far as the voltage apparently dropping with the heater fan "ON", the alternator or battery may be getting a bit weak. You could have the battery load tested, and if that checks out, monitor the system voltage at the battery, and see if your voltage is really dropping down to 10 Volts. Does it lose voltage when revved up, or just at idle? If it is losing voltage at the battery with the engine revved up a bit, it sounds like a weak alternator.

Check any and all ground wires/straps for integrity, tightness, and freedom from corrosion, the extra lead from the negative battery cable to the radiator support, and the strap from the back of the RH cylinder head (V8?) to the cab. (A bad ground connection can cause weird voltage problems.)

Just bought a lifetime warrentied alternator from O'Riellys for $75. Old one is 16 years old and 166,000 miles, can't ask for much more out of it, replacing before the REALLY cold weather hits.

Good luck.

mojomdw

Pitch

Posted 11-19-2004 at 05:34:06
[Reply] [No Email]I don't know that there really is a problem. I just never recall having a vehicle that the needle flucates on before. My van stays rock steady no matter what electrical equipment is running and does not register more than a momentary drop with any load.This acts the same weather at idle or at hiway speed. I will check all the ground straps.